HARVARD UNIVERSITY, MASSACHUSETTS, USA and UNIVERSITY OF EXETER, SOUTH WEST ENGLAND, UK. A fabric that can change its appearance when pressure or heat is applied. This new discovery can lead to the manufacturing of shirts that can change their colors when there is muscle tension or alerts the wearers when there is heat strain.

The principal investigator Peter Vukusic and team were inspired by a tropical fruit commonly known as the Bastard Hogberry. It is a South American tropical plant whose vivid color can easily deceive birds into eating and propagating its seed. This bright blue fruit is low in nutritional content but it is effective in mimicking its more nutritious and fleshy competitor. It does not change its color but the combination of its properties with an elastic material can result to a fiber that can be stretched into numerous different colors.

The cells on the seed of the fruit’s skin has a curved repeating pattern that interpose with light waves. Thus, creating colors similar to the bright colors that we see in soap bubbles. The ability of its surface structure to manipulate light made it an interesting pick.

It is by wrapping multiple layers of polymer around a glass core that is later etched away, that the photonic fibers are made. The color of the fiber is determined by the thickness of the layers. As the material is being stretched, spectrum of colors become visible. The fibers are versatile and can be used as smart sports textiles that can change color in areas with muscle tension or they can be wound to coat complex shapes.